src/test/ui/duplicate_entry_error.rs

// normalize-stderr-test "loaded from .*libstd-.*.rlib" -> "loaded from SYSROOT/libstd-*.rlib"
// note-pattern: first defined in crate `std`.

// Test for issue #31788 and E0152

#![feature(lang_items)]

use std::panic::PanicInfo;

#[lang = "panic_impl"]
fn panic_impl(info: &PanicInfo) -> ! {
//~^ ERROR: found duplicate lang item `panic_impl`
    loop {}
}

fn main() {}